Biodiversity: Introduction
Unit
1
:
Humans
and
Ecosystems
• Main themes:
Biodiversity,
Ecosystem services,
Sustainable development,
Climate change
9 weeks
2 assessments – one test and one project
Climate change
• Conclusions from the graphs ?
• Action- 17th Sept – Assembly
• Impacts of climate change on biodiversity &
ecosystems (and therefore us)
Levels of
Biological
organisation
Quick Quiz
1. How many species are there on the
planet ?
2. How many does ’science’ know about ?
3. How many more do we find each year ?
4. Which groups of organisms have the
most species in them ?
5. How old is life on earth ?
6. Where are the most biodiverse regions
on the planet ?
7. How did you get your answer ?
Biodiversity
•
•
•
•
The variety of life on Earth
Product of c. 4 billion years of evolution
1.2-1.8 million species described
7.5 -15 (100 ?) million species total ????
How come we don’t know ?
• New species continually discovered
/described, c. 18,000 per year
• 36 new Mammal species
• Where would you look to find new species ?
How many do we know about…
•
•
•
•
•
70 % of Plants are known & described
50 % ofAlgae
22 % fof single celled protozoa
12 % of animals
7 % of fungi
Bioluminescent Mushroom
(Discovered 2011)
(Some fruiting bodies of Mycena luxaeterna growing on a rotten
branch. © Cassius V. Stevani/IQ-USP, Brazil)
Mindoro Stripe faced fruit bat
Styloctenium mindorensis
98 new species
of beetle found
in Indonesia
Further reading
• http://www.bbc.com/earth/story/20150119how-to-discover-a-new-species
• http://www.esf.edu/top10/default.htm
Exploring Biodiversity
• http://www.iucnredlist.org/species-of-theday/archives
• Select a species, and bring the info to class
next time
The Red List
• global conservation status
of plant and animal
species
• IUCN
• Science based
• Classifies species
according to categories
• www.iucnredlist.org
One way of looking at this diversity…
Taxonomy
Taxonomy is the science of classification
For what reasons do we need to classify
organisms ?
Why classify ?
• After 3 billion years of evolution, there are c. 10-100 million
species of organisms living on earth
• If we are to talk about them and understand their roles in
ecosystems, then it is important that each has its own name.
• Uses include conservation, medicine, pest control, agriculture,
ecological studies on all levels
What to call a species ?
Before 1750, scientific names could be really
cumbersome:
Apis pubescens, thorace subgriseo,
abdomine fusco, pedibus posticis glabris
utrinque margine ciliatis
And any scholar could change them as they saw fit.
Modern hierarchical classification
• Species are classified into groups called TAXA
(singular = taxon)
• Based on important features that are shared
by the members of the group
– E.g. birds have wings, beaks and feathers
• The highest level is the KINGDOM
Hierarchical
classification
KPCOFGS
Kids playing catch on freeway
get squashed
Amimal example Plant Example
Kingdom
Phylum
Class
Order
Family
Genus
Species
Common
name
Animalia
Chordata
Mammalia
Primates
Hominidae
Homo
sapiens
Human
Plantae
Angiospermophyta
Dicotyledonae
Ranales
Rannunculacae
Ranunculus
acris
Meadow buttercup
(smörblomma)
Some rules
• Both the genus and species are printed in italics (or
underlined)
• The Genus, but not the species, has an initial capital letter.
• Species is spelled the same in both singular and plural.
• The plural of Genus is Genera
• The full name has an authority after it. e.g. L. is for Linneus
What is the“biodiversity crisis”?
• Extinction: death of all individuals of a species
• Extinctions are a normal part of the history of life
• 99 % of all species that have existed are now
extinct...
• BUT: Humans are causing extinctions at a
tremendous rate.
• ~100 times faster than expected without human
activity
• parallels or exceeds previous mass extinction
events
•
What if extinction > speciation?
Species diversity in
different groups of
organisms
Species extinctions
Planetary boundaries
Stockholm Resilience
centre- Science, Jan
2015